@p5
Name] = @p1) AND ([PostTime] = @p2) AND ([Message] = @p3) AND (NOT ([IsReplied] = 1)) AND ([Reply] IS NULL) 0; Scale = 0) [00000000-0000-0000-0000-000000000000] = 0; Scale = 0) [ghgh]
rec = 0; Scale = 0) [2007-8-16 10:20:09] = 0; Scale = 0) [ghj] c = 0; Scale = 0) [True] = 0; Scale = 0) [qqq]
odel: AttributedMetaModel Build: 3.5.20706.1
k] WHERE ([ID] = @p0) AND ([UserName] = @p1) AND ([PostTime] = @p2) AND ([Message] = @p3) AND (NOT ([IsR 0; Scale = 0) [158ec941-13ff-4093-bd8b-9fceae152171] = 0; Scale = 0) [44]
rec = 0; Scale = 0) [2007-8-16 9:56:19] = 0; Scale = 0) [44] = 0; Scale = 0) [222]
odel: AttributedMetaModel Build: 3.5.20706.1
今天就讲到这里，下次将系统介绍查询句法。
一步一步学Linq to sql（四）：查询句法
2007-10-18 09:00 作者： lovecherry 出处： 天极网 责任编辑：>dizzarz select
描述：查询顾客的公司名、地址信息 查询句法：
var 构建匿名类型1 = from c in ctx.Customers
select new {
公司名 = c.CompanyName, 地址 = c.Address };
对应SQL：
SELECT [t0].[CompanyName], [t0].[Address] FROM [dbo].[Customers] AS [t0] 描述：查询职员的姓名和雇用年份 查询句法：
var 构建匿名类型2 = from emp in ctx.Employees select new {
姓名 = emp.LastName + emp.FirstName, 雇用年 = emp.HireDate.Value.Year }; 对应SQL：
SELECT [t0].[LastName] + [t0].[FirstName] AS [value], DATEPART(Year, [t0].[HireDate]) AS [value2] FROM [dbo].[Employees] AS [t0]
描述：查询顾客的ID以及联系信息(职位和联系人) 查询句法：
var 构建匿名类型3 = from c in ctx.Customers
select new {
ID = c.CustomerID, 联系信息 = new
{
职位 = c.ContactTitle, 联系人 = c.ContactName } };
对应SQL：
SELECT [t0].[CustomerID], [t0].[ContactTitle], [t0].[ContactName] FROM [dbo].[Customers] AS [t0] 描述：查询订单号和订单是否超重的信息 查询句法：
var select带条件 = from o in ctx.Orders select new {
订单号 = o.OrderID,
是否超重 = o.Freight > 100 ? \是\否\ };
对应SQL：
SELECT [t0].[OrderID], (CASE
WHEN [t0].[Freight] > @p0 THEN @p1 ELSE @p2
END) AS [value]
FROM [dbo].[Orders] AS [t0]
-- @p0: Input Currency (Size = 0; Prec = 19; Scale = 4) [100] -- @p1: Input String (Size = 1; Prec = 0; Scale = 0) [是] -- @p2: Input String (Size = 1; Prec = 0; Scale = 0) [否]
where
描述：查询顾客的国家、城市和订单数信息(可以使用sql语句来表示)，要求国家是法国并且订单数大于5 查询句法：
// var result = (from m in methods // where m.IsStatic != true // select m.Name).Distinct();
var 多条件 = from c in ctx.Customers
where c.Country == \ select new {
国家 = c.Country, 城市 = c.City,
订单数 = c.Orders.Count }; 对应SQL：
SELECT [t0].[Country], [t0].[City], ( SELECT COUNT(*)
FROM [dbo].[Orders] AS [t2]
WHERE [t2].[CustomerID] = [t0].[CustomerID] ) AS [value]
FROM [dbo].[Customers] AS [t0]
WHERE ([t0].[Country] = @p0) AND ((( SELECT COUNT(*)
FROM [dbo].[Orders] AS [t1]
WHERE [t1].[CustomerID] = [t0].[CustomerID] )) > @p1)
-- @p0: Input String (Size = 6; Prec = 0; Scale = 0) [France] -- @p1: Input Int32 (Size = 0; Prec = 0; Scale = 0) [5]
orderby
描述：查询所有没有下属雇员的雇用年和名，按照雇用年倒序，按照名正序 查询句法：
var 排序 = from emp in ctx.Employees where emp.Employees.Count == 0
orderby emp.HireDate.Value.Year descending, emp.FirstName ascending select new {
雇用年 = emp.HireDate.Value.Year, 名 = emp.FirstName };
对应SQL：
SELECT DATEPART(Year, [t0].[HireDate]) AS [value], [t0].[FirstName] FROM [dbo].[Employees] AS [t0] WHERE ((
SELECT COUNT(*)
FROM [dbo].[Employees] AS [t1]
WHERE [t1].[ReportsTo] = [t0].[EmployeeID] )) = @p0
ORDER BY DATEPART(Year, [t0].[HireDate]) DESC, [t0].[FirstName] -- @p0: Input Int32 (Size = 0; Prec = 0; Scale = 0) [0]
分页
描述：按照每页10条记录，查询第二页的顾客 查询句法：
var 分页 = (from c in ctx.Customers select c).Skip(10).Take(10); 对应SQL：